For an acoustic frequency less than 24 kHz, existing video and voice play devices and receiving apparatuses can be fully used, and specially-customized loudspeakers and microphones are not needed. This acoustic frequency cannot be easily perceived by people's ears, and does not cause too much influences on people's daily life; therefore, acoustic communication is widely applied. However, in a conventional field of acoustic communications technologies, a processing process is complex, and a bit error rate is relatively high, which suppresses acoustic communication efficiency, and hinders development of acoustic communication.
The orthogonal frequency division multiplexing (OFDM) technology is a multi-carrier digital modulation technology. Although the concept of OFDM exists for a long time, people recently realizes that OFDM is a good way to implement high-speed bidirectional wireless data communication, and OFDM is commonly known in electronic communication and is not involved in the field of acoustic communication technologies. How to apply the OFDM technology in the acoustic communication to simplify a processing process, reduce a bit error rate, and improve communication efficiency is a technical problem currently to be solved.